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Detection of miRNA Targets in High-throughput Using the 3'LIFE Assay
Published on: May 25, 2015
Let-7 microRNAs are developmentally regulated in circulating human erythroid cells
Seung-Jae Noh1, Samuel H Miller, Y Terry Lee
1Molecular Medicine Branch, National Institute of Diabetes, Digestive, and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA. nohseung@niddk.nih.gov
Journal of Translational Medicine
|November 27, 2009
Summary
MicroRNA let-7 levels increase in adult red blood cells, coinciding with human fetal-to-adult hemoglobin switching. This suggests a role for microRNAs in developmental gene regulation.
Area of Science:
- Molecular Biology
- Genetics
- Developmental Biology
Background:
- MicroRNAs (miRNAs) are small non-coding RNAs regulating gene expression in eukaryotes.
- They play crucial roles in development and cell differentiation.
- Erythrocyte miRNA profiles were analyzed to link changes in abundance to hemoglobin switching.
Purpose of the Study:
- To investigate microRNA expression profiles in human erythroid cells at birth versus adulthood.
- To determine if miRNA abundance changes correlate with the developmental shift in hemoglobin types.
Main Methods:
- MicroRNA expression profiling using custom spotted arrays (474 human miRNAs).
- Analysis of total RNA from adult and cord blood erythroid cells.
- Validation of key findings using quantitative PCR.
Main Results:
- 37 microRNAs were significantly upregulated and 4 downregulated in adult erythroid cells.
- The let-7 miRNA family showed consistent, significant upregulation in adult cells (4.5-18.4 fold increase).
- Ten let-7 target genes were downregulated in adult cells, consistent with let-7 activity.
Conclusions:
- A distinct pattern of let-7 miRNA upregulation occurs in circulating erythroid cells during human fetal-to-adult development.
- These findings suggest let-7 miRNAs are involved in the developmental transition associated with hemoglobin switching.
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